Gamma-ray production in neutral-current neutrino-oxygen interactions at energies above 200 MeV

Abstract

We report the results of a calculation of the neutrino- and antineutrino-induced gamma-ray production cross section for oxygen target. Our analysis is focused on the kinematical region of neutrino energy larger than ~200MeV, in which single-nucleon knockout is known to be the dominant reaction mechanism. The numerical results have been obtained using a realistic model of the target spectral function, extensively tested against electron-nucleus scattering data. We find that at neutrino energy 600 MeV the fraction of neutral-current interactions leading to emission of gamma-rays of energy larger than 6 MeV is ~41%, and that the contribution of the p_{3/2} state is overwhelming.Comment: Invited paper to NUFACT 11, XIIIth International Workshop on Neutrino Factories, Super beams and Beta beams, 1-6 August 2011, CERN and University of Genev